Woven wire screen



March 23, 1937. s, PALMER 2,074,665

WOVEN WIRE SCREEN Filed Aug. 2, 1954 I nventor S. HPQl/fl er Attorney Patented Mar. 23, 1937 UNlTED STATES PATENT OFFICE.

WOVEN wnm scenes Samuel H. Palmer, Portland, Greg.- Application August 2, 1934, Serial No. 738,117

Claims.

It is also an important object of my invention to provide a screen of the type described which is capable of being made with either square or oblong mesh, and wherein the longitudinal and transverse wires are so engaged with each other as to prevent and minimize shifting of the wires relative to each other, so as to make an ,efiicient screen for use on revolving, vibrator or shaker machines.

It is also an important object of my invention to provide a screen of the type described above wherein the wearing surface is distributed over the greater part of the screen so as to increase the length of service thereof.

It is also an important object of my invention to provide a screen of the type described above which has formations therein for holding the longitudinal and transverse wires spaced with respect to each other which are capable of being manufactured into the wires while the wires are cold, thereby eliminating thenecessity and desirability of annealing the wires before crimping and rehardening thereafter, thereby considerably reducing the cost of manufacture, while providing a superior screen in which .both the longitudinal and the transverse wires are 0 high carbon material.

Other objects and advantages of my invention will be apparent from a reading of the following description in connection with the drawing, wherein for. purposes of illustration I have shown a preferred embodiment of my invention. Inthe drawingz- Figure 1 is a plan view of a portion of a screen constructed in accordance with the invention.

Figure 2 is a transverse sectional view taken through Figure 1 approximately on the line 2 2. .In some screens known to me the formations of the intersecting wires are such as to demand an oblong mesh, whereas the formations of the intersecting wires of the present invention admit of making screens with either oblong or square or transversely elongated mesh. Other prior screens involve two different types of wire, notably a high carbon wire for the wires which run in one direction and a low carbon wire for the wires which run in the other direction, so that there is an inequality as to strength; and some of the latter screens have comparatively large weft wires but comparatively small warp wires.

constructions which encourage lack of strength and uniform and quick wear. Other screens depend for their efficient character'upon proper heat treatment of the wires before and after fabrication, some of the latter screens having in their final form warp wires which are tough and weft Wires which are ductile, in contrast to the equally tough warp and weft wires obtaining in the case of the present invention.

It is obvious that special heat treating be- 7 fore and after fabrication, and subsequent rolling and other operations which are employed in the formation of some prior screens greatly addto the expense of production while in most cases detracting from that-degree of durability and strength which is obtained in the screen of the invention wherein I have made possible the manufacturing cold without annealing and rehardening, of a uniformly strong and long and even wearing screen composed of equally tough and hard warp and weft wires of equal size.

It will be observed that my screen has a practically flat or smooth side and an exceptionally rough side, so that the screen may be used for both light and rough and heavy work. The rough side may be used where exceptional speed of screening is desired, and the rough side of my screen is achieved not by providing sharp quickly wearing crimps which must be formed by heat treatment or cold pressing which would weaken the crimps, but by specially formed crimps which form an adequate-receptacle for-the intersecting wiresv and which are nevertheless by reason of their form capable of being manufactured cold without weakening-the wires. -By reason of the fact that the inherent sp tension of high carbon wires is not, in the invention removed by heat treating or by violent straining incident to some methods of cold formation,

' the natural springiness of the wire remains and the construction" of the intersecting portions of the wires in my screen, definitely precludes shifting of the wires relative to each other in normal seryica. As a result of the spring character of the wirewhich is retained in conjunction with the special formations of the intersecting portions of the wire, wear at these points is reduced I to a heretofore unknown minimum, and the wear preserved uniform throughout the screen.

Another advantage of the screen of my invention lies in the fact that whfle in the case of forming known types of screens, in which the warp and weft wires have different types of crimps, the

6 three-foot length tailings from the loom are wasted whereas in the case of the invention these tailings are saved and are used for the wires in the next screen, since the warp and weft wires are of the same gauge and have identical crimps.

Outstanding advantages of the screen of the invention and the method of its formation may be summed up as follows:-

(1) The screen is made throughout of high test carbon steel wire or bars.

(2) The screen is .fabricated throughout entirely by cold pressing and weaving, no heat treatment of the original high carbon wires or bars being employed.

(3) The screen is characterized by the shallow 0 crimp and by the gradual arch form of the pressed wires or bars used in weaving the screen.

(4) The gradual arch employed gives the screen a practically flat surface on one side, all of such gradual arches being on only one side of the screen; and at the same time, since all of the shallow crimps are on the opposite side of the screen, this opposite side of the screen is given a very rough surface. In this way a double purpose-screen is provided in one manufacturing operation,'the fiat surface being particularly adapted for screening exceptionally tough or abrasive substances, since the wear on the screen is distributed equally on all parts of the surface of the screen thereby securing long life of the screen.

The opposite and rough side of the screen is particularly adapted for screening less abrasive substances and will give a higher passage ratio than the flat side, and the rough side is also adapted for use when utmost efficiency in screening is desired and the consideration of wear is less important.

(5) The employment of the gradual arch and the shallow crimp in conjunction with high carbon wires which have inherent springiness, provide a screen which is practically flat on one side and quite rough on the opposite side, in which the wire joints are bound by reason of their formation and by reason of the springiness of the wires, so that the screen is rigid and frictional wear of the joints while the screen is under the strains and stressesof vibration in use, is very greatly reduced. 1

All of these advantages may be achieved in screens made of either round wire or of square or oblong section bars.

Referring in detail to the drawing, the numeral 5 generally designates the screen which is formed of longitudinal wires or bars 6 and transverse wires or bars 'I. It has already been stated 0 herein that the bars 6 and Imay be either round, square, or of oblong section and be of wire stock or of bar stock of different gauges according to the service for which the screen is designed.

Each of the wires or bars 6 and 1 is formed with a plurality of uniformly curved flat arches 8, all of which extends in the same direction and each pair of arches is connected together by a crimp 9 which is very gradually formed in the wire or bar and these crimps all extend in an opposite direction to thearches and aswill be seen from Figure 2 each arch of each wire or bar has its central portion passing over a wire or bar or the other set and resting in a crimp of said bar of the other set, the crimp 9 at the ends of said arches receiving other wires or bars of the other set. The hollow of the crimps 8 is adequate in view of the springy character of the intersecting wires to positively assure a tight Joint between the intersecting wires which preclude shifting of the wires relative to each other even in the most severe service. Because there is a lack of shifting between the intersecting wires, frictional wear between the wires is reduced to a minimum. It will be observed that the very gradual deformation of the wires required to produce the shallow crimps 9 makes it possible to construct the crimps in the wires by the cold pressing, even though the wires be and are provided to be of high carbon steel, entirely without annealing and/or rehardening, so that the crimps and arches are as strong as any other part of the wire and not subject to deterioration under strain and flexing.

As already explained, the use of high carbon uniform cross section bars of wires of equal tensile strength produces maximum strength and wearing qualities, and the special crimps and arches forming the joints between intersecting wires or rods also add to the rigidity of the screen, much increase the wearing qualities of the screen, and provide a relatively smooth side and an extraordinarily rough side on the one screen.

It will be observed in Figure 2 that the arches 8 are .very gradually curved in contour and that the crimps 9 produce the protuberance I0 on the opposite side of the wire, and that all of the wires are uniformly formed in this manner, so that the smooth arches 8 are on the upper side of the screen and the relatively sharp protuberances ill on the lower or opposite side of the screen, as earlier stated herein.

Although I have shown and described herein a preferred embodiment of my invention, it is to be definitely understood that I do not desire to limit the application of the invention thereto, and any change or changes may be made in materials and in the structure and arrangement of parts, within the spirit of the invention and the scope of the subioined claims.

What is claimed is:

1. A screen of the class described, comprising two sets of rods, one set being arranged at right angles to the other set, and each rod being composed of a plurality of uniformly curved elongated arches and relatively short and gradually formed shallow crimps connecting the arches together, the arches all curving in one direction and the crimps extending in an opposite direction, each arch of the bar having its central portion located in a crimp of a bar of the other set, the arches in all the bars being on one side of the screen, the protuberances formed by the crimps on the other side of the screen.

2. A screen of the character described having a relatively smooth side and a relatively rough side, said screen comprising two sets of crossed spring tension high carbon wires, one set being arranged at right angles to the other set, each wire being formed with cold-pressed gradual longitudinal arches, said arches bowing on the smooth side of the screen, the terminals of adjacent arches defining relatively shallow crimps on the opposite or relatively rough side of the screen, said crimps thereby being coincident with the intersections of adjacent arches, said sets of wires being woven with the wires of each set alternately overlying and underlying the wires of the other set, and the midpoints of the arches in each set overlying the intersections of the arches in the other set.

3. A woven screen formed exclusively of cold pressed high carbon wire, said screen having its warp wires and the weft wires of said screen being of substantially the same gauge, each warp wire and each weft wire being formed with lon- 5 gitudinal gradual arches bowed on one side of the screen only with adjacent arches defining intersections, shallow crimps on the opposite side of said screen, said shallow crimps being defined by said intersections, the concave side of the 10 arches of the wires overlying the concave side of the crimps throughout the screen, thereby providing said screen with a relatively smooth side corresponding to said arches and a relatively rough side corresponding to said crimps. i5 4. A woven wire screen composed of crossed spring high carbon cold formed wires of similar gauge, said screen exhibiting a relatively smooth side and a relatively rough side, said wires each comprising a series of shallow arches bowing on 20 the smooth side of the screen and a series of shallow crimps extending on the rough side of the screen and resulting Irom the formation oi. adjacent arches, the concave side of the arches of the wires overlying the concave side of the crimps throughout the screen, whereby the 5 crossed wires are prevented from shifting relative to each other.

5. A method of making a woven-wire screen of high carbon spring steel crossed wires of substantially-the same gauge, said method comprising cold pressing said wires so as to form shallow arches bowing in one direction only and shallow crimps between said arches extending in the opposite direction only, then crossing the arched and crimped wires in such manner that the con- 15 cave side of the crimps of each vwire underlying the concave side of the arches of the wires transverse thereto.

SAMUEL H. PALMER. 20 

